The administration of blood and/or blood components is common in the treatment of patients suffering from disease or blood loss. Rather than infuse whole blood, it is more typical that individual components be administered to the patient in need. For example, administration (infusion) of platelets is often prescribed for cancer patients whose ability to make platelets has been compromised by chemotherapy. Red blood cells are typically administered to patients who have suffered a loss of blood, anemia or other disorders. Infusion of plasma may also be prescribed for therapeutic reasons and, more recently, the harvesting and administration of stem cells has received widespread interest within the medical community. Thus, it is often desirable to separate and collect a blood component, (e.g., red blood cells, platelets, plasma, stem cells) from whole blood and then treat the patient with the specific blood component. The remaining components may be returned to the donor or collected for other uses.
There are several factors to be considered in the separation, collection and storage of blood components for subsequent transfusion. For example, the presence of white blood cells (e.g., leukocytes) in a blood component collected for administration is often considered to be undesirable as such leukocytes can trigger an adverse response in the recipient-patient. As a result, blood components are often “leukoreduced” prior to transfusion. Also, the presence of certain antibodies in plasma has been correlated with the occurrence of TRALI (transfusion-related acute lung injury) in some patients receiving blood components such as red blood cells. Consequently, while plasma is present to some degree in transfusible red blood cells and platelets, it is desirable to reduce the amount of plasma in the red blood cell or platelet preparation.
Red blood cells are often stored for long periods of time prior to transfusion. In this case, the environment in which the cells are stored may have to be carefully controlled to optimize or at least maintain cell properties required for effective transfusion. For example, it is usually desirable to at least maintain adenosine triphosphate (ATP) and 2,3-diphosphoglycerate (2,3-DPG) levels and limit hemolysis during storage.
Additive solutions useful for improving the storage environment of red blood cells are disclosed, for example, in pending U.S. application Ser. No. 12/408,483, filed Mar. 20, 2009 (Mayaudon et al.), and a continuation-in-part of the '483 application which is being filed on the same day as the present application and is entitled “Red Blood Cell Storage Medium for Extended Storage” (Mayaudon et al.), which serial number has not yet been assigned but which is identified by Applicant's reference number F-6542 CIP, which applications are incorporated by reference herein in their entireties.
Other additive solutions for improving the storage environment for red blood cells (and other components) are disclosed, for example, in U.S. Pat. No. 5,250,303 (Meryman), incorporated by reference herein, which discloses solutions for the extended storage of red blood cells. The solutions disclosed therein are generally chloride-free, hypotonic solutions which provide for the long-term storage of red blood cells. According to U.S. Pat. No. 5,250,303 to Meryman, the chloride-free, effectively hypotonic solutions induce a “chloride-shift” which, in turn, leads to a rise in the intracellular pH of the red blood cells. Also, according to Meryman, the rise in intracellular pH appeared to be correlated with rise in ATP and/or 2,3 DPG and, thus, prolonged storage times.
Although, Meryman recognized the benefit of using hypotonic solutions to extended storage of red blood cells generally, Meryman did not appreciate the benefits of using selected relative amounts of additive solution and plasma in the storage environment for the red cells, nor did Meryman describe systems for providing such red blood cell products.
Thus, there still exists a need for methods and systems that provide readily transfusible red blood cells whereby the red blood cell environment can be controlled and enhanced by preserving the red blood cells and reducing the potential of TRALI.